Is package patching available only for registered partner accounts ? I have freeware created developer account. As I see I can not create this or I am doing something wrong ?
Without being a partner it won't work at all on a public developer org. You'll get only this:
So you could sign-up. The basic process shouldn't be too hard.
If you are a partner you have it by default. You think. But it's only a "light version"....
All that patch orgs are used to execute push upgrades. Those push upgrades even for partners come in two flavors: Push-Minor and Push-Major.
With push-minor you can only change existing components, which is in fact not very helpful for most use cases.
Probably only with push-major, you can do what you really want: https://developer.salesforce.com/releases/release/Winter13/PUSH+Major+Upgrade
To get Push-Major activated you have to either pass the security review or you have to register into the ISV-Programme. I tried this for a free App ( https://appexchange.salesforce.com/listingDetail?listingId=a0N3000000B5SYEEA3 ) but they refused it. At least in Germany they seem to accept only paid solutions, no free apps, no even freemium models (e.g. one paid package and parallel a less-featured free second package). This is very sad.
I'm trying to find out other options here ( https://salesforce.stackexchange.com/questions/41968/push-major-upgrades-before-security-review-possible ) - but nothing so far...
Then finally, if you have passed the review or joined ISV, you can log a case and ask them to activate it.
So an unfortunate, it's not so easy to get a full featured push upgrade process up and running...